53c7xx.c

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	ncrcurrent[0] = hostdata->NOP_insn;
	ncrcurrent[1] = 0xdeadbeef;
    }
    ncrcurrent[0] = ((DCMD_TYPE_TCI|DCMD_TCI_OP_JUMP) << 24) | DBC_TCI_TRUE;
    ncrcurrent[1] = (u32) virt_to_bus (hostdata->script) +
	hostdata->E_wait_reselect;
    hostdata->reconnect_dsa_head = 0;
    hostdata->addr_reconnect_dsa_head = (u32) 
	virt_to_bus((void *) &(hostdata->reconnect_dsa_head));
    hostdata->expecting_iid = 0;
    hostdata->expecting_sto = 0;
    if (hostdata->options & OPTION_ALWAYS_SYNCHRONOUS) 
	hostdata->initiate_sdtr = 0xffff; 
    else
    	hostdata->initiate_sdtr = 0;
    hostdata->talked_to = 0;
    hostdata->idle = 1;
}

/* 
 * Function : static int clock_to_ccf_710 (int clock)
 *
 * Purpose :  Return the clock conversion factor for a given SCSI clock.
 *
 * Inputs : clock - SCSI clock expressed in Hz.
 *
 * Returns : ccf on success, -1 on failure.
 */

static int 
clock_to_ccf_710 (int clock) {
    if (clock <= 16666666)
	return -1;
    if (clock <= 25000000)
	return 2; 	/* Divide by 1.0 */
    else if (clock <= 37500000)
	return 1; 	/* Divide by 1.5 */
    else if (clock <= 50000000)
	return 0;	/* Divide by 2.0 */
    else if (clock <= 66000000)
	return 3;	/* Divide by 3.0 */
    else 
	return -1;
}
    
/* 
 * Function : static int NCR53c7x0_init (struct Scsi_Host *host)
 *
 * Purpose :  initialize the internal structures for a given SCSI host
 *
 * Inputs : host - pointer to this host adapter's structure
 *
 * Preconditions : when this function is called, the chip_type 
 * 	field of the hostdata structure MUST have been set.
 *
 * Returns : 0 on success, -1 on failure.
 */

int 
NCR53c7x0_init (struct Scsi_Host *host) {
    NCR53c7x0_local_declare();
    int i, ccf;
    unsigned char revision;
    struct NCR53c7x0_hostdata *hostdata = (struct NCR53c7x0_hostdata *)
	host->hostdata[0];
    /* 
     * There are some things which we need to know about in order to provide
     * a semblance of support.  Print 'em if they aren't what we expect, 
     * otherwise don't add to the noise.
     * 
     * -1 means we don't know what to expect.
     */
    int val, flags;
    char buf[32];
    int expected_id = -1;
    int expected_clock = -1;
    int uninitialized = 0;
#ifdef NO_IO_SPACE
    int expected_mapping = OPTION_MEMORY_MAPPED;
#else
    int expected_mapping = OPTION_IO_MAPPED;
#endif
    for (i=0;i<7;i++)
	hostdata->valid_ids[i] = 1;	/* Default all ID's to scan */

    /* Parse commandline flags */
    if (check_setup_strings("noasync",&flags,&val,buf))
    {
	hostdata->options |= OPTION_NO_ASYNC;
	hostdata->options &= ~(OPTION_SYNCHRONOUS | OPTION_ALWAYS_SYNCHRONOUS);
    }

    if (check_setup_strings("nosync",&flags,&val,buf))
    {
	hostdata->options &= ~(OPTION_SYNCHRONOUS | OPTION_ALWAYS_SYNCHRONOUS);
    }

    if (check_setup_strings("nodisconnect",&flags,&val,buf))
	hostdata->options &= ~OPTION_DISCONNECT;

    if (check_setup_strings("validids",&flags,&val,buf))
    {
	for (i=0;i<7;i++) 
		hostdata->valid_ids[i] = val & (1<<i);
    }
 
    if  ((i = check_setup_strings("next",&flags,&val,buf)))
    {
	while (i)
		setup_used[--i] = 1;
    }

    if (check_setup_strings("opthi",&flags,&val,buf))
	hostdata->options = (long long)val << 32;
    if (check_setup_strings("optlo",&flags,&val,buf))
	hostdata->options |= val;

    NCR53c7x0_local_setup(host);
    switch (hostdata->chip) {
    case 710:
    case 770:
    	hostdata->dstat_sir_intr = NCR53c7x0_dstat_sir_intr;
    	hostdata->init_save_regs = NULL;
    	hostdata->dsa_fixup = NCR53c7xx_dsa_fixup;
    	hostdata->init_fixup = NCR53c7x0_init_fixup;
    	hostdata->soft_reset = NCR53c7x0_soft_reset;
	hostdata->run_tests = NCR53c7xx_run_tests;
	expected_clock = hostdata->scsi_clock;
	expected_id = 7;
    	break;
    default:
	printk ("scsi%d : chip type of %d is not supported yet, detaching.\n",
	    host->host_no, hostdata->chip);
	scsi_unregister (host);
	return -1;
    }

    /* Assign constants accessed by NCR */
    hostdata->NCR53c7xx_zero = 0;			
    hostdata->NCR53c7xx_msg_reject = MESSAGE_REJECT;
    hostdata->NCR53c7xx_msg_abort = ABORT;
    hostdata->NCR53c7xx_msg_nop = NOP;
    hostdata->NOP_insn = (DCMD_TYPE_TCI|DCMD_TCI_OP_JUMP) << 24;
    if (expected_mapping == -1 || 
	(hostdata->options & (OPTION_MEMORY_MAPPED)) != 
	(expected_mapping & OPTION_MEMORY_MAPPED))
	printk ("scsi%d : using %s mapped access\n", host->host_no, 
	    (hostdata->options & OPTION_MEMORY_MAPPED) ? "memory" : 
	    "io");

    hostdata->dmode = (hostdata->chip == 700 || hostdata->chip == 70066) ? 
	DMODE_REG_00 : DMODE_REG_10;
    hostdata->istat = ((hostdata->chip / 100) == 8) ? 
    	ISTAT_REG_800 : ISTAT_REG_700;

/* We have to assume that this may be the first access to the chip, so
 * we must set EA in DCNTL. */

    NCR53c7x0_write8 (DCNTL_REG, DCNTL_10_EA|DCNTL_10_COM);


/* Only the ISTAT register is readable when the NCR is running, so make 
   sure it's halted. */
    ncr_halt(host);

/* 
 * XXX - the NCR53c700 uses bitfielded registers for SCID, SDID, etc,
 *	as does the 710 with one bit per SCSI ID.  Conversely, the NCR
 * 	uses a normal, 3 bit binary representation of these values.
 *
 * Get the rest of the NCR documentation, and FIND OUT where the change
 * was.
 */

#if 0
	/* May not be able to do this - chip my not have been set up yet */
	tmp = hostdata->this_id_mask = NCR53c7x0_read8(SCID_REG);
	for (host->this_id = 0; tmp != 1; tmp >>=1, ++host->this_id);
#else
	host->this_id = 7;
#endif

/*
 * Note : we should never encounter a board setup for ID0.  So,
 * 	if we see ID0, assume that it was uninitialized and set it
 * 	to the industry standard 7.
 */
    if (!host->this_id) {
	printk("scsi%d : initiator ID was %d, changing to 7\n",
	    host->host_no, host->this_id);
	host->this_id = 7;
	hostdata->this_id_mask = 1 << 7;
	uninitialized = 1;
    };

    if (expected_id == -1 || host->this_id != expected_id)
    	printk("scsi%d : using initiator ID %d\n", host->host_no,
    	    host->this_id);

    /*
     * Save important registers to allow a soft reset.
     */

    /*
     * CTEST7 controls cache snooping, burst mode, and support for 
     * external differential drivers.  This isn't currently used - the
     * default value may not be optimal anyway.
     * Even worse, it may never have been set up since reset.
     */
    hostdata->saved_ctest7 = NCR53c7x0_read8(CTEST7_REG) & CTEST7_SAVE;
    revision = (NCR53c7x0_read8(CTEST8_REG) & 0xF0) >> 4;
    switch (revision) {
	case 1: revision = 0;    break;
	case 2: revision = 1;    break;
	case 4: revision = 2;    break;
	case 8: revision = 3;    break;
	default: revision = 255; break;
    }
    printk("scsi%d: Revision 0x%x\n",host->host_no,revision);

    if ((revision == 0 || revision == 255) && (hostdata->options & (OPTION_SYNCHRONOUS|OPTION_DISCONNECT|OPTION_ALWAYS_SYNCHRONOUS)))
    {
	printk ("scsi%d: Disabling sync working and disconnect/reselect\n",
							host->host_no);
	hostdata->options &= ~(OPTION_SYNCHRONOUS|OPTION_DISCONNECT|OPTION_ALWAYS_SYNCHRONOUS);
    }

    /*
     * On NCR53c700 series chips, DCNTL controls the SCSI clock divisor,
     * on 800 series chips, it allows for a totem-pole IRQ driver.
     * NOTE saved_dcntl currently overwritten in init function.
     * The value read here may be garbage anyway, MVME16x board at least
     * does not initialise chip if kernel arrived via tftp.
     */

    hostdata->saved_dcntl = NCR53c7x0_read8(DCNTL_REG);

    /*
     * DMODE controls DMA burst length, and on 700 series chips,
     * 286 mode and bus width  
     * NOTE:  On MVME16x, chip may have been reset, so this could be a
     * power-on/reset default value.
     */
    hostdata->saved_dmode = NCR53c7x0_read8(hostdata->dmode);

    /* 
     * Now that burst length and enabled/disabled status is known, 
     * clue the user in on it.  
     */
   
    ccf = clock_to_ccf_710 (expected_clock);

    for (i = 0; i < 16; ++i) 
	hostdata->cmd_allocated[i] = 0;

    if (hostdata->init_save_regs)
    	hostdata->init_save_regs (host);
    if (hostdata->init_fixup)
    	hostdata->init_fixup (host);

    if (!the_template) {
	the_template = host->hostt;
	first_host = host;
    }

    /* 
     * Linux SCSI drivers have always been plagued with initialization 
     * problems - some didn't work with the BIOS disabled since they expected
     * initialization from it, some didn't work when the networking code
     * was enabled and registers got scrambled, etc.
     *
     * To avoid problems like this, in the future, we will do a soft 
     * reset on the SCSI chip, taking it back to a sane state.
     */

    hostdata->soft_reset (host);

#if 1
    hostdata->debug_count_limit = -1;
#else
    hostdata->debug_count_limit = 1;
#endif
    hostdata->intrs = -1;
    hostdata->resets = -1;
    memcpy ((void *) hostdata->synchronous_want, (void *) sdtr_message, 
	sizeof (hostdata->synchronous_want));

    NCR53c7x0_driver_init (host);

    if (request_irq(host->irq, NCR53c7x0_intr, SA_SHIRQ, "53c7xx", host))
    {
	printk("scsi%d : IRQ%d not free, detaching\n",
		host->host_no, host->irq);
	scsi_unregister (host);
	return -1;
    } 

    if ((hostdata->run_tests && hostdata->run_tests(host) == -1) ||
        (hostdata->options & OPTION_DEBUG_TESTS_ONLY)) {
    	/* XXX Should disable interrupts, etc. here */
	scsi_unregister (host);
    	return -1;
    } else {
	if (host->io_port)  {
	    host->n_io_port = 128;
	    request_region (host->io_port, host->n_io_port, "ncr53c7xx");
	}
    }
    
    if (NCR53c7x0_read8 (SBCL_REG) & SBCL_BSY) {
	printk ("scsi%d : bus wedge, doing SCSI reset\n", host->host_no);
	hard_reset (host);
    }
    return 0;
}

/* 
 * Function : static int ncr53c7xx_init(Scsi_Host_Template *tpnt, int board, 
 *	int chip, u32 base, int io_port, int irq, int dma, long long options,
 *	int clock);
 *
 * Purpose : initializes a NCR53c7,8x0 based on base addresses,
 *	IRQ, and DMA channel.	
 *	
 * Inputs : tpnt - Template for this SCSI adapter, board - board level
 *	product, chip - 710
 * 
 * Returns : 0 on success, -1 on failure.
 *
 */

int 
ncr53c7xx_init (Scsi_Host_Template *tpnt, int board, int chip, 
    u32 base, int io_port, int irq, int dma, long long options, int clock)
{
    struct Scsi_Host *instance;
    struct NCR53c7x0_hostdata *hostdata;
    char chip_str[80];
    int script_len = 0, dsa_len = 0, size = 0, max_cmd_size = 0,
	schedule_size = 0, ok = 0;
    void *tmp;
    unsigned long page;

    switch (chip) {
    case 710:
    case 770:
	schedule_size = (tpnt->can_queue + 1) * 8 /* JUMP instruction size */;
	script_len = NCR53c7xx_script_len;
    	dsa_len = NCR53c7xx_dsa_len;
    	options |= OPTION_INTFLY;
    	sprintf (chip_str, "NCR53c%d", chip);
    	break;
    default:
    	printk("scsi-ncr53c7xx : unsupported SCSI chip %d\n", chip);
    	return -1;
    }

    printk("scsi-ncr53c7xx : %s at memory 0x%x, io 0x%x, irq %d",
    	chip_str, (unsigned) base, io_port, irq);
    if (dma == DMA_NONE)
    	printk("\n");
    else 
    	printk(", dma %d\n", dma);

    if (options & OPTION_DEBUG_PROBE_ONLY) {
    	printk ("scsi-ncr53c7xx : probe only enabled, aborting initialization\n");
    	return -1;
    }

    max_cmd_size = sizeof(struct NCR53c7x0_cmd) + dsa_len +
    	/* Size of dynamic part of command structure : */
	2 * /* Worst case : we don't know if we need DATA IN or DATA out */
		( 2 * /* Current instructions per scatter/gather segment */ 
        	  tpnt->sg_tablesize + 
                  3 /* Current startup / termination required per phase */
		) *
	8 /* Each instruction is eight bytes */;

    /* Allocate fixed part of hostdata, dynamic part to hold appropriate
       SCSI SCRIPT(tm) plus a single, maximum-sized NCR53c7x0_cmd structure.

       We need a NCR53c7x0_cmd structure for scan_scsis() when we are 
       not loaded as a module, and when we're loaded as a module, we 
       can't use a non-dynamically allocated structure because modules
       are vmalloc()'d, which can allow structures to cross page 
       boundaries and breaks our physical/virtual address assumptions
       for DMA.

       So, we stick it past the end of our hostdata structure.

       ASSUMPTION : 
       	 Regardless of how many simultaneous SCSI commands we allow,
	 the probe code only executes a _single_ instruction at a time,